Abstract
Anode reactor powder cores are used to protect Thyristor Valves of HVDC (High-Voltage Direct Current)transmission systems. They must have a long life under special conditions of high frequency and high magnetic flux density. Thus, they should have the properties of low core loss, constant permeability, high saturated flux density, and excellent heat resistance.
To develop them, we studied on formation methods and compositions of uniform inorganic insulation films on each powder, and on selection and additive conditions of resin. As the results, we have developed the new anode reactor powder cores which shows specific resistivity of more than 1 Ωm, which is above twenty times of usual powder cores, and saturation flux density of more than 1T. They show scarcely increase of core loss after 4000 hours at 423 K, which means that they indicate excellent heat resistance.
